Field of the Invention
The present invention relates to the field of conveyor technology. It relates to a conveyor installation for the transportation of articles, in particular goods, along a predefined path.
Discussion of Related Art
For the automatic conveyance of articles, such as for example items of clothing suspended on hangers, along rails led through a space, the prior art has disclosed a multiplicity of systems which fall under the term “Power and free” and which are distinguished by the fact that the articles suspended on running carriages are moved forward by drivers which run in parallel and which are driven and which are in engagement and which, if the running carriage encounters an obstruction, automatically pass out of engagement and are moved past the stopped running carriage.
Document DE 10 2005 006 455 A1 discloses a transport system for suspended articles, in particular for items of clothing suspended on hangers, having a transport rail, having a drive chain which is arranged so as to be movable in a conveying direction in the transport rail and which has downwardly projecting drivers, and having holding elements for the articles, which holding elements are mounted in the transport rail, below the drive chain, by way of running rollers and which are movable in the conveying direction by way of the drive chain. The transport system is distinguished by the fact that the drivers are of bolt-like form, in that the holding elements are mounted in the transport rail in pendular fashion only about one pair of rollers and have upwardly protruding projections for engaging into the drive chain between two adjacent drivers, and in that, between the transport rail and the holding elements, there are provided means which prevent projection and driver from passing out of engagement in the presence of a predefined maximum inclination of the holding element relative to a normal with respect to the transport rail in a vertical transport plane spanned by the conveying direction.
Document DE 10 2011 119 411 A1 discloses a retroactively installable stopper unit for a suspended conveyor, which stopper unit transports a pawl-type driver, in an at least unilaterally open slot of a support rail on which hangers are transported in sliding fashion by way of pawl-type drivers, downstream in a conveying direction which is oriented parallel to the longitudinal direction of the support rail. The stopper unit comprises a guide which is fastenable to the suspended conveyor, a carriage which has an abutment section, wherein the carriage is, by way of the guide, mounted so as to be movable preferably linearly in a transverse direction which is oriented transversely with respect to the longitudinal direction; and a drive which is coupled to the carriage and which is designed such that, during the activation thereof, said drive deploys the carriage from a release position, in which the abutment section of the carriage does not project beyond the rail, such that the hangers can pass by the carriage, along the transverse direction into a stop position, in which the abutment section projects beyond the support rail, preferably over the entire width thereof, wherein, when the drive is activated, in the event of a force acting in the transverse direction, the carriage can be retracted into the release position, and in the event of a force acting exclusively in the longitudinal direction, the carriage remains in its present position.
The document DE 203 17 972 U1 describes a suspended conveyor installation having a conveyor rail, having a driveable conveyor device which is arranged above the conveyor rail, having pawl-type drivers which are attached to the conveyor device and which are oriented relative to the conveyor rail and which serve for transporting hanger hooks, which are situated displaceably on the conveyor rail, in a conveying direction, wherein each pawl-type driver has a carrier connected to the conveyor device and has a pawl, which pawl has a driver hook which follows in the conveying direction and which pawl is hinged at the carrier by way of a pivot spindle which is arranged laterally with respect to and above the conveyor rail and at an acute angle (d) of at most 60° with respect to the conveying direction. The document U.S. Pat. No. 6,367,612 B1 discloses an extendable driver for an overhead accumulating conveyor system (“power and free”) which comprises a body section composed of a rectangular cylinder which is equipped with a spring and slider element within the cylinder. If a force greater than the static spring force acts on the slider element, the slider element retracts into the body section, such that the structural height of the driver is reduced. Owing to its automatic retraction, the retractable driver does not require any modification to the driven and free rails or to the running carriages.
All known systems operate with engagement configurations which are duly released when an obstruction is encountered but which then retract again into a stable engagement basic position. Owing to this “monostable” mode of operation, the use of the known systems is restricted. Furthermore, the monostable mode of operation is associated with considerable noise generation, for example because, when a stopped running carriage is “passed over” by the successive drivers which are in each case deflected and retract into their initial state again, a rattling noise is generated.